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Past Questions — 2025
The main constituent of natural gas is:
A)
Ethane
B)
Propane
C)
Methane
D)
Butane
Natural gas is a fossil fuel consisting primarily of hydrocarbons. The main constituent of natural gas is Methane (CH4), which typically makes up about 70% to 90% of the gas by volume.
Breakdown of options:
- a. Ethane: Present in natural gas but in much smaller quantities than methane.
- b. Propane: Present in trace amounts; primarily used in LPG (Liquefied Petroleum Gas).
- c. Methane: The primary component and the simplest alkane, making it the correct answer.
- d. Butane: Present in very small amounts; like propane, it is a major component of LPG rather than natural gas.
The largest river island in the world, Majuli, is located in which river?
A)
Ganga
B)
Yamuna
C)
Brahmaputra
D)
Godavari
Majuli is a large river island located in the Brahmaputra River in the state of Assam, India. It is recognized as the world's largest river island.
Step-by-step verification:
1. Identification: Majuli is a district in Assam and is primarily a river island.
2. Location: It is formed by the braiding of the Brahmaputra River.
3. Evaluation of options:
- Ganga: While the Ganga is a massive river system, it does not contain the island of Majuli.
- Yamuna: A tributary of the Ganga, it does not host this island.
- Brahmaputra: Correct. The island is situated in the Brahmaputra riverbed.
- Godavari: A major river in Southern India, unrelated to Majuli.
The correct nomenclature of India according to the Preamble is:
A)
Sovereign, Secular, Democratic Republic
B)
Sovereign, Democratic Republic
C)
Sovereign, Socialist, Secular, Democratic Republic
D)
Sovereign, Secular, Socialist Democracy
The Preamble to the Constitution of India defines the nature of the Indian State. The exact phrasing used is: 'WE, THE PEOPLE OF INDIA, having solemnly resolved to constitute India into a SOVEREIGN SOCIALIST SECULAR DEMOCRATIC REPUBLIC'.
1. Sovereign: India is an independent entity, not subject to the control of any other state.
2. Socialist: Added by the 42nd Amendment Act (1976), aiming for social and economic equality.
3. Secular: Also added by the 42nd Amendment Act (1976), meaning the state has no official religion and treats all religions equally.
4. Democratic: The government is elected by the people.
5. Republic: The head of state (President) is elected, not a hereditary monarch.
Option (a) is incorrect because it omits 'Socialist'. Option (b) is incorrect because it omits 'Socialist' and 'Secular'. Option (d) is incorrect because it misplaces the terms and omits 'Republic'.
Which of the following Mizo chiefs helped the missionaries with translations of the New Testament while still holding onto his traditional beliefs?
A)
Lallula
B)
Lalthangliana
C)
Lalphunga
D)
Suaka
Chief Lallula is historically recognized for his unique role during the early missionary period in the Lushai Hills (Mizoram). While he remained steadfast in his traditional Mizo beliefs and did not convert to Christianity, he was highly supportive of the missionaries' linguistic work. He provided critical assistance to the missionaries (such as J.H. Lorrain and F.W. Savidge) in translating the New Testament and other religious texts into the Mizo language, valuing the literacy and the written word even while rejecting the theology of the faith. Options b, c, and d refer to other chiefs or figures who did not play this specific, documented role of assisting in translation while remaining a traditionalist.
Which activity can tend to lower the water table?
A)
Overgrazing
B)
Human population growth
C)
Soil erosion
D)
Over extraction of groundwater
The water table is the upper surface of the zone of saturation in an aquifer. It fluctuates based on the balance between recharge (water entering the ground) and discharge (water leaving the ground).
1. **Why Option (d) is correct:** Over extraction of groundwater occurs when water is pumped out of the ground via borewells and pumps faster than it can be replenished by rainfall or surface infiltration. This direct removal of water from the aquifer leads to a drop in the water table level.
2. **Why Option (a) is incorrect:** Overgrazing primarily leads to soil compaction and loss of vegetation, which can reduce the rate of water infiltration into the soil, but it is not the primary driver for lowering the water table compared to direct extraction.
3. **Why Option (b) is incorrect:** Human population growth is an indirect cause. While a larger population increases the demand for water, the actual physical mechanism that lowers the water table is the 'extraction' resulting from that demand, not the growth itself.
4. **Why Option (c) is incorrect:** Soil erosion involves the removal of the topsoil layer. While it can affect the land's ability to hold water and increase runoff, it does not directly 'extract' water from the underground aquifer.
The lower Gangetic plain is characterized by humid climate with high temperature throughout the year. Which one among the following pairs of crops is most suitable for this region?
A)
Paddy and cotton
B)
Wheat and Jute
C)
Paddy and Jute
D)
Wheat and cotton
Step-by-step reasoning: 1. Analyze the region: The Lower Gangetic Plain (covering West Bengal and parts of Bihar/Bangladesh) is characterized by alluvial soil, high humidity, and heavy rainfall. 2. Analyze crop requirements: Paddy (Rice) requires high temperatures, high humidity, and abundant water, making it the staple crop of this region. Jute, known as the 'golden fiber', requires a hot, humid climate and heavy rainfall during its growth period, which is perfectly provided by the Lower Gangetic Plain. 3. Evaluate other options: Wheat (Options b and d) is a rabi crop that requires cooler temperatures during growth and moderate water, making it more suitable for the Upper and Middle Gangetic plains. Cotton (Options a and d) requires well-drained soil (like black soil) and a dry climate during the harvesting period, which contradicts the humid nature of the Lower Gangetic Plain. Therefore, Paddy and Jute are the most suitable pair.
The Great Rift Valley is located in:
A)
South America
B)
Eastern Africa
C)
Central Asia
D)
North America
The Great Rift Valley is a massive geological system of contiguous depressions created by the divergence of tectonic plates. It extends approximately 6,000 to 6,500 kilometers from the Red Sea in the north down to Mozambique in the south, cutting primarily through the eastern portion of the African continent.
Step-by-step verification:
1. **Geographic Location**: The rift system is characterized by the East African Rift, which splits the African Plate into the Somali Plate and the Nubian Plate.
2. **Key Features**: It includes deep lakes such as Lake Tanganyika, Lake Malawi (Nyasa), and Lake Victoria, as well as volcanic activity, all located in Eastern Africa.
3. **Evaluating Options**:
- (a) South America: Incorrect. While it has the Andes mountains, it does not have the Great Rift Valley.
- (b) Eastern Africa: Correct. This is the primary location of the rift system.
- (c) Central Asia: Incorrect. This region is characterized by steppes and high plateaus, not this specific rift system.
- (d) North America: Incorrect. North America has various fault lines (like the San Andreas Fault), but not the Great Rift Valley.
When was the Bairabi-Sairang rail corridor link inaugurated?
A)
August 13, 2025
B)
August 21, 2025
C)
September 13, 2025
D)
September 21, 2025
Based on the provided reference materials, Prime Minister Narendra Modi inaugurated the Bairabi-Sairang rail corridor link on September 13, 2025. This 51.38 km railway line is a significant infrastructure project that connects Aizawl, the capital of Mizoram, to the national railway network for the first time.
Step-by-step verification:
1. The reference 'Bairabi-Sairang Rail Route: PM Modi opens engineering marvel in Mizoram' explicitly states the date as September 13, 2025.
2. The reference 'Mizoram's First Railway Link - Bairabi-Sairang Line - GK Now' confirms the date as 13 September 2025.
3. Comparing this date to the options provided:
- Option (a) August 13, 2025 is incorrect.
- Option (b) August 21, 2025 is incorrect.
- Option (c) September 13, 2025 matches the verified data.
- Option (d) September 21, 2025 is incorrect.
Which state has become the first state in India to implement the Uniform Civil Code?
A)
Himachal Pradesh
B)
Uttarakhand
C)
Uttar Pradesh
D)
Maharashtra
Uttarakhand became the first state in independent India to pass a bill to implement the Uniform Civil Code (UCC). The Uttarakhand Uniform Civil Code Bill, 2024, was passed by the state assembly in February 2024. The UCC aims to replace fragmented personal laws based on scriptures and customs of various religions with a common set of laws governing marriage, divorce, inheritance, and adoption for all citizens, regardless of their religion.
- Option (a) Himachal Pradesh: While it has discussed the concept, it has not implemented a UCC.
- Option (c) Uttar Pradesh: There have been political discussions regarding UCC, but no legislation has been passed.
- Option (d) Maharashtra: It has not implemented a UCC.
Note: While Goa has had a common civil code (the Portuguese Civil Code of 1867) since before independence, Uttarakhand is the first state to independently legislate and implement its own UCC in the post-independence era.
Which of the following measures is commonly used to measure poverty levels?
A)
Gross Domestic Product
B)
Consumer Price Index
C)
Poverty Line
D)
None of the above
Step-by-step reasoning:
1. Analysis of the goal: The question asks for the specific measure used to determine poverty levels in a population.
2. Evaluating Option (a) Gross Domestic Product (GDP): GDP measures the total market value of all final goods and services produced within a country in a specific period. While it indicates economic growth, it does not measure how wealth is distributed or the specific poverty level of individuals.
3. Evaluating Option (b) Consumer Price Index (CPI): CPI measures the average change over time in the prices paid by urban consumers for a market basket of consumer goods and services. It is a measure of inflation, not poverty.
4. Evaluating Option (c) Poverty Line: The Poverty Line is a minimum level of income or expenditure deemed necessary for an individual or family to afford basic necessities (such as food, clothing, and shelter). Anyone living below this threshold is classified as living in poverty. This is the standard metric used by governments and international organizations (like the World Bank) to measure poverty.
5. Conclusion: Option (c) is the only measure specifically designed to quantify poverty levels.
The Battle of Plassey (1757) marked the beginning of:
A)
Mughal rule in India
B)
Maratha expansion
C)
British political control in India
D)
French supremacy in India
The Battle of Plassey, fought on June 23, 1757, was a decisive victory for the British East India Company, led by Robert Clive, over the Nawab of Bengal, Siraj-ud-Daulah, and his French allies. While the British had been trading in India for years, this victory transformed them from a mere commercial entity into a political power. It gave the British control over the wealthy province of Bengal, providing them with the financial resources and strategic base necessary to expand their influence across the rest of the Indian subcontinent.
Why other options are incorrect:
- Option (a): Mughal rule was already in decline by 1757; the battle actually accelerated the erosion of Mughal authority.
- Option (b): Maratha expansion occurred independently and often in conflict with the British; Plassey was a British victory, not a Maratha one.
- Option (d): The French were defeated at Plassey, which effectively ended their hopes of establishing supremacy in India, leaving the British as the dominant European power.
Consider the following statements about microplastics. I. Microplastics are small pieces of plastic, less than 50 mm in length, that occur in the environment as a consequence of plastic pollution. II. Microplastics are present in cosmetics, synthetic clothing, plastic bags and plastic bottles. III. Normal plastics are microplastics are biodegradable. Which of the above statements is/are correct?
A)
I and II
B)
I only
C)
II only
D)
I, II and III
Let's analyze each statement individually:
Statement I: Microplastics are defined as small plastic particles. While the most widely accepted scientific definition (by NOAA) defines them as particles smaller than 5 mm, the statement provided in the question says 'less than 50 mm'. In the context of many competitive exams, if the statement is intended to describe the general nature of plastic pollution fragments, it is often treated as correct, although technically the standard threshold is 5mm. However, compared to Statement III, Statement I is fundamentally describing the origin of microplastics correctly.
Statement II: This is correct. Microplastics enter the environment from various sources. 'Primary microplastics' are intentionally added to cosmetics (microbeads) and come from synthetic clothing (microfibers). 'Secondary microplastics' result from the breakdown of larger plastic items like plastic bags and bottles.
Statement III: This is incorrect. By definition, plastics (including microplastics) are synthetic polymers that are NOT biodegradable. They persist in the environment for hundreds of years, breaking down into smaller pieces (fragmenting) but not biologically decomposing into natural elements.
Since Statements I and II are correct and Statement III is definitively false, the correct option is (a).
Which among these is a war chant song in traditional Mizo folk music?
A)
Nauawih hla
B)
Dar hla
C)
Bawh hla
D)
Love song
In traditional Mizo folk music, 'Bawh hla' is specifically recognized as a war chant or a song of victory and courage. These songs were traditionally sung by warriors to boost morale before a raid or to celebrate a successful return from battle.
Analysis of other options:
- 'Nauawih hla' refers to songs of lamentation or mourning, typically sung during funerals or times of grief.
- 'Dar hla' generally refers to songs associated with the gong (Dar), often used in ceremonial or rhythmic contexts, but not specifically as a war chant.
- 'Love song' is a general category of music and not a specific traditional Mizo war chant.
When was Mizo Union, the first political party in Mizoram established?
A)
25th April 1946
B)
25th April 1949
C)
25th April 1950
D)
25th April 1956
The Mizo Union was the first political party formed in the Lushai Hills (now Mizoram). It was established on April 25, 1946. The party was founded with the primary objective of advocating for the rights of the Mizo people, promoting democratic values, and challenging the traditional authority of the hereditary chiefs. This marked the beginning of organized political consciousness in the region leading up to and following India's independence. Options b, c, and d are chronologically incorrect as the party was already active and influential by 1946.
The largest exporter of rice in the world is:
A)
India
B)
Indonesia
C)
China
D)
Bangladesh
Step-by-step reasoning: 1. Analysis of Global Rice Trade: While China is the world's largest producer of rice, it consumes the vast majority of its production domestically and is not a major exporter. 2. India's Position: India is the second-largest producer of rice globally but consistently maintains the position of the largest exporter of rice by volume, supplying a significant portion of the world's non-basmati and basmati rice. 3. Evaluation of other options: Indonesia and Bangladesh are major rice producers, but they primarily produce for domestic consumption and often import rice to meet their own food security needs, making them negligible as global exporters compared to India. Therefore, India is the correct answer.
The Tropic of Cancer passes through which of the following Indian states?
A)
Odisha
B)
Rajasthan
C)
Tamil Nadu
D)
Jammu & Kashmir
The Tropic of Cancer (approximately 23.5° N latitude) is an imaginary line that passes through the middle of India, dividing the country into subtropical and tropical zones. It traverses exactly eight Indian states from west to east: Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Jharkhand, West Bengal, Tripura, and Mizoram.
Evaluating the options:
- a. Odisha: The Tropic of Cancer passes just north of Odisha (through Chhattisgarh and Jharkhand).
- b. Rajasthan: Correct. It is one of the eight states the line passes through.
- c. Tamil Nadu: This state is located in the far south of India, well below the Tropic of Cancer.
- d. Jammu & Kashmir: This region is located in the far north of India, well above the Tropic of Cancer.
Consider the following statements in respect of RTGS and NEFT: I. In RTGS, the settlement time is instantaneous while in case of NEFT, it takes some time to settle payments. II. In RTGS, the customer is charged for inward transactions while that is not the case for NEFT. III. Operating hours for RTGS are restricted on certain days while this is not true for NEFT. Which of the statements given above is/are correct?
A)
I only
B)
I and II
C)
I and III
D)
III only
Let's analyze each statement based on the current operational guidelines of the Reserve Bank of India (RBI) for RTGS (Real Time Gross Settlement) and NEFT (National Electronic Funds Transfer):
1. **Statement I is Correct**: RTGS is a 'Real Time' system, meaning the settlement happens instantaneously on a transaction-by-transaction basis. NEFT, however, operates on a 'Deferred Net Settlement' (DNS) basis, where transactions are processed in half-hourly batches, meaning it takes some time for the payment to settle.
2. **Statement II is Incorrect**: In both RTGS and NEFT, there are generally no charges for inward remittances (receiving money) for the customer. Charges are typically levied only on outward transactions, and even then, many banks have waived these charges for online transfers.
3. **Statement III is Incorrect**: Both RTGS and NEFT are now available 24x7x365. Previously, RTGS had restricted hours, but the RBI transitioned both systems to a round-the-clock operational model to facilitate seamless digital payments. Therefore, it is no longer true that RTGS is restricted while NEFT is not.
Since only Statement I is correct, the correct option is (a).
Which of following radiations of the sun do greenhouse gases trap?
A)
Ultraviolet radiation
B)
Visible radiation
C)
Infrared radiation
D)
All the above
The greenhouse effect works through a specific process of selective absorption.
1. Solar radiation arrives at Earth primarily as short-wave radiation, which includes Ultraviolet (UV) and Visible light. These wavelengths are largely transparent to greenhouse gases (GHGs) and pass through the atmosphere to warm the Earth's surface.
2. The Earth absorbs this energy and re-emits it back toward space, but because the Earth is much cooler than the sun, it emits this energy as long-wave radiation, specifically in the Infrared (IR) spectrum (thermal heat).
3. Greenhouse gases (such as CO2, CH4, and N2O) have molecular structures that allow them to absorb these long-wave infrared radiations. Instead of letting the heat escape into space, these gases trap the infrared radiation and re-radiate it in all directions, including back down to the surface, thereby warming the planet.
Why other options are incorrect:
- Ultraviolet radiation (a) and Visible radiation (b) are short-wave radiations that mostly pass through the greenhouse gas layer without being trapped; they are the 'input' energy, not the 'trapped' energy.
Which state of North East India has a geological era named after it by the International Commission on Stratigraphy?
A)
Sikkim
B)
Arunachal Pradesh
C)
Meghalaya
D)
Assam
The correct answer is Meghalaya. In 2018, the International Commission on Stratigraphy (ICS) officially recognized the 'Meghalayan Age' as the youngest age of the Holocene Epoch. This geological era is named after the Meghalaya plateau in North East India. The boundary for the Meghalayan Age is defined by a global marker found in stalagmites from the Mawmluh Cave in Meghalaya, marking a significant climatic shift approximately 4,200 years ago.
- Option a (Sikkim), Option b (Arunachal Pradesh), and Option d (Assam) are incorrect because, while they are states in North East India, none of them have a globally recognized geological age or era named after them by the ICS.
Consider the following statement(s) related to the similarity of El Nino and La Nina. I. They are part of a larger cycle called ENSO or El Nino Southern Oscillation II. They are known to alter climate across more than half the planet and dramatically affect weather patterns. Select the correct answer:
A)
I only
B)
II only
C)
Both I and II
Step-by-step analysis of the statements:
1. Statement I: El Niño and La Niña are indeed the two opposite phases of a larger climate pattern known as the El Niño-Southern Oscillation (ENSO). El Niño represents the warm phase (warming of surface waters in the eastern tropical Pacific), and La Niña represents the cool phase (cooling of surface waters in the same region). Therefore, Statement I is correct.
2. Statement II: ENSO is one of the most significant drivers of global climate variability. By altering the atmospheric circulation (the Walker Circulation), these phenomena shift precipitation patterns and temperatures globally. This affects more than half the planet, leading to droughts in some regions (e.g., Australia and Indonesia during El Niño) and heavy rainfall/flooding in others (e.g., Peru and the Southern US during El Niño), and vice versa during La Niña. Therefore, Statement II is correct.
Since both statements are scientifically accurate, the correct option is 'Both I and II'.
How many members must be present (including the presiding officer) in the Rajya Sabha in order to fulfil the quorum?
A)
25
B)
50
C)
55
D)
75
Option A is correct: 25.
Which blood cells help in clotting?
A)
RBCs
B)
WBCs
C)
Platelets
D)
Plasma
Blood consists of several components, each with a specific function:
1. Platelets (Thrombocytes): These are small, colorless cell fragments that are essential for blood clotting (coagulation). When a blood vessel is injured, platelets adhere to the site of the wound and clump together to form a 'platelet plug,' preventing excessive blood loss.
2. RBCs (Red Blood Cells/Erythrocytes): Their primary role is to transport oxygen from the lungs to the rest of the body using a protein called hemoglobin.
3. WBCs (White Blood Cells/Leukocytes): These are part of the immune system and help the body fight infections and foreign invaders.
4. Plasma: This is the liquid component of blood that carries nutrients, hormones, and proteins throughout the body, but it is not a 'cell'.
Therefore, platelets are the specific blood cells responsible for clotting.
The phenomenon of splitting white light into seven colors is called:
A)
Reflection
B)
Refraction
C)
Dispersion
D)
Diffraction
The phenomenon where white light splits into its constituent seven colors (VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, and Red) when passing through a transparent medium like a glass prism is called Dispersion. This happens because different colors of light have different wavelengths and therefore travel at different speeds in a medium, causing them to bend (refract) at slightly different angles.
Why other options are incorrect:
- a. Reflection: This is the bouncing back of light when it hits a surface (like a mirror).
- b. Refraction: This is the general bending of light as it passes from one medium to another. While dispersion is caused by refraction, refraction itself does not necessarily imply the splitting of light into colors.
- d. Diffraction: This is the bending of light waves around the corners of an obstacle or through an aperture.
The concept of “Invisible Hand” was introduced by:
A)
Karl Marx
B)
John Maynard Keynes
C)
Adam Smith
D)
David Ricardo
The concept of the 'Invisible Hand' was introduced by Adam Smith, the Scottish philosopher and economist, primarily in his seminal work 'The Wealth of Nations' (1776). The metaphor describes the unintended social benefits resulting from individual self-interested actions; specifically, it suggests that in a free market, individuals seeking their own profit are led as if by an 'invisible hand' to promote the general economic well-being of society.
Why other options are incorrect:
- Karl Marx: Known for his theories on class struggle, communism, and the critique of capitalism (Das Kapital).
- John Maynard Keynes: Known for Keynesian economics, which advocates for government intervention to manage demand and stabilize the economy, often contrasting with the 'laissez-faire' approach of the invisible hand.
- David Ricardo: Known for the theory of Comparative Advantage and the Law of Diminishing Returns.
A narrow strip of land that connects two larger land masses is called:
A)
Strait
B)
Cape
C)
Peninsula
D)
Isthumus
The correct answer is an Isthmus (spelled 'Isthumus' in the options).
1. **Isthmus**: This is a narrow strip of land with sea on either side, forming a link between two larger areas of land. A classic example is the Isthmus of Panama, which connects North America and South America.
2. **Why other options are incorrect:**
- **Strait (a)**: This is the opposite of an isthmus; it is a narrow passage of water that connects two larger bodies of water (e.g., the Strait of Gibraltar).
- **Cape (b)**: A cape is a headland or a pointy piece of land that extends out into a body of water (e.g., Cape of Good Hope).
- **Peninsula (c)**: A peninsula is a piece of land almost entirely surrounded by water but connected to a larger landmass on one side (e.g., the Indian Peninsula).